1. Field of the Invention
This invention relates to sandwich glasses for use in front glass for automobiles, window glass for buildings, decorative glass, glass for the reflection or absorption of heat radiation and the like, and more particularly to a sandwich glass having excellent safety, durability, scuff resistance and penetration resistance.
2. Description of the Prior Art
In this type of the sandwich glass, various synthetic resins have hitherto been used as an intermediate layer. In such conventional sandwich glasses, however, there are scarcely those satisfying all of safety, durability, penetration resistance and scuff resistance. Particularly, even if the penetration resistance and scuff resistance are tentatively attained, it is more desirable to improve them.
In view of energy-saving, heat-absorbing or heat-reflecting glasses have recently been used as a window glass for usual houses or buildings. In the heat-absorbing glass, the glass itself or its surface is colored, while in the heat-reflecting glass, the surface of transparent or colored glass is provided with a thin layer of metal or metal oxide as a heat-reflecting layer.
However, not only the heat-absorbing and --reflecting glasses are very expensive, but also once they are broken, the broken glass pieces are scattered likewise the ordinary glass to cause a problem in view of the safety.
Furthermore, when a film for the reflection or absorption of heat radiation is affixed to the surface of the glass, the working is relatively simple and the effect on the prevention of the scattering of broken glass pieces is slightly developed. However, the film itself is poor in the durability, is apt to be peeled off and is low in the scuff resistance, so that it is required to replace the film with a new one every several years.
There have recently been popularized decorative glasses, wherein various designs such as drawings, pictures, photographs, letters and the like are applied to the surface of various window glasses or partition glasses. These decorative glasses are widely used as a window glass for the partition of bath room, child room and the like, glasses for skylight at a ceiling face, a display in shops or buildings, a show window, and further as a replacement for stained glass. In such a case, however, since the design is printed, applied or affixed to the surface of glass, there are caused the same drawbacks as in the aforementioned glass affixed with the heat-absorbing or --reflecting film, and particularly there is not a little problem in the durability and safety. Particularly, when the decorative glass is used for the partition of the bath room, since the atmosphere in the bath room is severe conditions of high temperature and high humidity, the design floats or peels off from the glass and also becomes discolored within 1-2 years. There are also the same drawbacks as in the decorative glass when a film printed with various designs is directly affixed to the glass surface.
Moreover, although it is possible either to affix a film including a colorant to glass surface for absorbing heat radiation, or to directly deposit a metal on the glass surface or affix a metal deposited film to the glass surface for providing an effect on the reflection of heat radiation or a conductivity, there are also caused the above drawbacks.